Self-pressurized deep ocean buoy



Sept 0, 1966 E. J. BECK, JR

SELFPRES SURIZED DEEP OCEAN BUOY Fil'ed May 26, 1964 Mam? I NVEN TOR.

United States Patent 3,273,181 SELF-PRESSURIZED DEEP OCEAN BUOY Earl I.Beck, Jr., 1323 W. Fir Ave., Oxnard, Calif. Filed May 26, 1964, Ser. No.370,383 6 Claims. (Cl. 98)

The invention described herein may be manufactured and used by or forthe Government of the United States of America for governmental purposeswithout the payment of any royalties thereon or therefor.

This invention relates generally to deep sea buoys and particularly toself-pressurized buoys capable of penetrating to great ocean depths andthen returning to the surface when their mission is accomplished.

In these days of enhanced oceanographic research, it is frequentlynecessary to lower instruments to great depths to obtain corings of theocean floor or for other pertinent information. In some cases, such asobtaining corin gs, it may be desired to have the instrument bearingbuoy return to the surface as soon as practicable whereas, in othercases, it may be desirable to retain the instrument on the bottom, orclosely adjacent thereto, for predetermined periods of time after whichthey may be allowed to return to the surface.

So long as such operations were conducted fairly near to the surface,these instrument-furnished buoys could be lowered from surface equipmentand placed in the desired position. As greater depths were encountered,the buoys became heavier and larger to withstand increased pressuresuntil their weight and the weight and size of the handling equipmentbecome prohibitive. Several types of such deep water buoys evolved. Oneconsisted of an underwater pontoon where positive buoying is provided byair or other low density gas enclosed in a heavy metal shell rigidenough to withstand the great pressure existing in the lower deeps. Thishollow pontoon could be filled with a cellular type of gas absorbingmaterial for further strengthening the enclosing shell. As greaterdepths were encountered, this type of buoy became objectionable due todifliculties of transporting and emplacing these buoys near the desiredlocation. Their recovery proved equally diflicult. Another type of buoyemployed gasoline or other low density liquids, usually of a hydrocarbonbase, enclosed in a semirigid vessel of synthetic rubber or othersuitable flexible, plastic material. Such buoys proved unsuitable due tothe dangers encountered in using the inflammable low density liquids,the fragility of the non-rigid containers and other disadvantages toonumerous to catalog.

A third form of underwater buoy evolved having a medium-thick, reducedweight, high strength shell enclosing a quantity of gas under highpressures. The static pressure required in this type would beapproximately equivalent or slightly greater than the hydrostaticpressures to be encountered in the ocean. Such buoys required specialequipment to transport and attain the gas pressures required and weresubject to explosion during handling at the surface.

From the above, it is most apparent that an urgent need exists for alight weight, easily handled, deep ocean buoy which will survive a tripto the deep ocean floor and back to the surface, remain successfullysubmerged for protracted periods and still retain sufiicient buoyancyfor surface return.

The principal object of my invention, therefore, is to provide alight-weight, thin wall deep ocean buoy which will pressurize itself asit descends to a pressure equivalent to the ambient Water pressure andwhich contains means to establish a positive buoyancy for its return tothe surface.

Another object is to provide such deep ocean buoy which may beconstructed of light weight materials not requiring specialmetallurgical characteristics such as high tensile or compressivestrengths coupled with noncorrodible properties.

Other objects, advantages and novel features of the invention willbecome apparent from the following detailed description of the inventionwhen considered in conjunction with the accompanying drawings wherein:

FIGURE 1 is a cross-sectional elevation of one type of prior art deepocean buoy;

FIG. 2 is a similar view of another type of prior art buoy; and

FIG. 3 is a partly cross-sectional elevation of my invention.

FIGURE 1 is a prior art type of deep ocean buoy having a thick, heavyshell 10 enclosing a quantity of air or other low density gas 11. Fillermaterial 12 which may be cellular wood, other suitable cellularmaterial, or lightweight rare metals having a density below that of seawater, is provided for additional pressure resistant purposes. Whilerealizing that such filler materials detract from the overall buoyancyof the device, the use of such materials in this type of buoy may bemandatory for preventing implosion at great depths.

FIGURE 2 is another prior art type of buoy having a medium thick shell15 enclosing a quantity of highly pressurized gas 16. Due to the highgas pressures unloaded, which must initially equal or exceed the waterpressures expected to be encountered, it is obvious that, for thegreater depths, the shell must be strengthened to resist explosion atthe surface, both initially and on the return trip, until it approachesthe shell of the previous type and all lower weight advantages are lost.

With reference now to FIG. 3, my improved deep ocean buoy 20 isillustrated having a valveless light weight shell 21, a quantity of gasor fluid 22, a vent 23, pay load 24, weight or anchor 25, cables 26connecting the buoy with its weights and payloads, and an insulatedunpr'essurized open container 27 for a highly vaporizable substance 28.

As there shown, the lightweight, stream-line shell can be constructed ofthin plates of light metals such as alloys of aluminum. The gas or fluid22 may be ordinary air at atmosphere pressure or it may be a combinationof other gases and water. The vent 23 is provided to allow ambient waterto enter the shell and keep it automatically pressurized at whateverdepth it may be immersed. It is also provided to allow the water in theshell to be expelled when full buoyancy is being established due to thedelayed or later action of the substance 28.

The weights and payload 24 and 25 are designed and calculated to causethe buoy to sink to the bottom and still, in some cases, be light enoughto be lifted when full buoyancy is established. In other cases, theweight or anchor may be releasably secured to the shell 21 by cables 26.The releasing device may be constructed for release after a certainpredetermined time or may otherwise be operated acoustically,mechanically, or electronically. The payload 24 may be suspended, asshown, or may be more closely attached to the shell, depending upon thetype of instrumentation utilized therein.

The substance 28 contained in its insulated, non-pressurized container27 may be liquid or solid nitrogen, hydrogen, or solid carbon dioxide.The choice of the material and the amount to be incorporated dependsupon the purpose and depth for which the buoy is to be used. Forcomparatively shallow depths, solid CO could well be used. The singlerequirement for proper functioning is that at the point of temperatureand pressure equilibrium, the substance 28 must not condense. Generally,

this means that when a gas is used it must be kept above its criticaltemperature. As set forth in the Handbook of Chemistry and Physics, somethirteen gases are available commercially with critical temperaturesbelow the freezing point of water, a minimum temperature for ocean use.

In actual use, the container of the substance 28 is em-- placed in thenose of the buoy and the vessel is readied for lowering into the water.As it slowly immerses, water enters the vent 23 and the internalpressure is equalized with external pressures. The substance 28 mayslowly evaporate until the buoy reaches the bottom. In the event theimmediate return of the buoy is desired, a liquid substance can be usedand spilled out of its container or otherwise caused to boil rapidly bythe shock of hitting the bottom or some timing device whereupon allwater is expelled, the buoy becomes positively buoyant, and returns tothe surface. When this approach is employed the opening in the container27 should be large enough to allow the liquid substance to be rapidlypoured into the shell when it is tipped. Where the approximate depth oftotal immersion is known, the quantity of the highly vaporizablesubstance 28 can be calculated to produce an internal pressure greaterthan ambient external pressure whereupon the expelled water and gas maybe utilized to give a jet effect through the vent which serves to breakthe buoy and its payload from the bottom. This feature is particularlydesirable when the payload comprises a corer which may become embeddedin the ocean bottom.

The weight of the substance 28 may be easily calculated in accordancewith the universal gas law:

For instance, when the lowest operating depth of 600 feet is to bereached and liquid nitrogen is to be used in a buoy having an internalvolume of 4 cubic feet and a weight of approximately 14 pounds (0.040thick walls).

be required but the net buoyancy for the sample buoy would still be 182pounds.

The exact arrangement of the triggering mechanism for obtaining fullevaporation or boiling of the expellent material is one of choice,principally depending on the designed purpose for which the buoy is tobe used. In the simplest case, the substance 28 would be allowed to boilslowly during descent of the buoy on its anchor and payload. In anothercase, the incoming water could be allowed to act as the triggeringmechanism. By compressing the initial air charge, the water wouldeventually rise to the level of the top of the container 27; heattransfer would suddenly be improved and the gas would boil rapidly,absorbing heat from the water, and establishing positive buoyancy in ashort period of time. In the above example, the time rate ofestablishing positive buoyancy could be cont-rolled by pressurizing theinitial charge of atmospheric air or introducing an initial quantity ofwater into the buoy. Various alternative timing methods could be devisedand used, such as mechanical timing means for dumping the substance 28into the sea water in the buoy, or other suitable chemical, electric, orpressure controlled means.

Obviously many modifications and variations of the present invention arepossible in the light of the above teachings. It is therefore'to beunderstood that within the scope of the appended claims the inventionmay be practiced otherwise than as specifically described I claim:

1. A self-pressurized lightweight deep ocean buoy comprising, incombination:

a lightweight metal hollow shell having an upper nose portion and alower tail portion, said shell being of greater length than its majorcross-sectional diameter;

a single vent formed in said shell, said vent being located in the lowertail portion of said shell for admitting ambient water under pressure tothe interior of said hollow shell;

oceanographic instrument means attached to the lower portion of saidshell;

a quantity of highly vaporizable substance carried interiorly of thenose portion of said hollow shell adapted to release a volume of highpressure gas sufiicient to establish a positive buoyancy of said deepocean buoy enabling it to return the said instruments to the surface;and

said quantity of highly vaporizable substance being contained in aninsulated open container which is mounted in the nose portion of saidshell.

2. A self-pressurized lightweight buoy as claimed in claim 1 wherein thequantity of said substance is a function of the desired time ofimmersion of said deep ocean buoy.

3. A self-pressurized lightweight buoy as claimed in claim 1 wherein thequantity of said substance is a function of the immersion depth attainedby said deep ocean buoy.

4. A self-pressurized deep ocean buoy comprising:

a hollow shell having upper and lower portions;

said shell having a vent located in its lower portion for allowingambient water to enter and exit said shell;

an open container means located within the upper portion of said shellfor containing a highly vaporizable substance which, upon evaporation,is capable of forcing ambient water to exit through said vent at thelowest operating depth of said buoy; and

the opening in said container means being of a size to allow a liquidsubstance to be poured into the shell when said shell is sufficientlytipped.

5. A self-pressurized deep ocean buoy as claimed in claim 4 wherein:

a highly vaporizable liquid substance is disposed within said opencontainer means, said liquid substance being of a type and quantity toforce ambient water from the shell at the lowest operating depth of saidbuoy.

6. A self-pressurized lightweight deep ocean buoy comprising:

a lightweight hollow shell having an upper nose portion and a lower tailportion, said shell being of a greater length than its majorcross-sectional diameter;

said shell having only one vent, said vent being valveless and locatedin said lower tail portion for allowing ambient water to enter and exitsaid shell;

an open container means located within said upper nose portion forpouring a liquid therefrom into said shell when the shell is tippedsufliciently; and

a highly vaporizable liquid substance disposed within said container,said liquid substance being of a type and quantity to force ambientwater from the'shell at the lowest operating depth of said buoy.

12/1962 Testa 114-54 6/ 1963 Tatnall et al. 9-8 X MILTON BUCHLER,Primary Examiner.

FERGUS S. MIDDLETON, Examiner.

R. G. BESHA, T. MAJOR, Assistant Examiners.

1. A SELF-PRESSURIZED LIGHTWEIGHT DEEP OCEAN BUOY COMPRISING, INCOMBINATION: A LIGHTWEIGHT METAL HOLLOW SHEEL HAVING AN UPPER BOREPORTION AND A LOWER TAIL PORTION, SAID SHEEL BEING OF GREATER LENGTHTHAN ITS MAJOR CROSS-SECTIONAL DIAMETER; A SINGLE VENT FORMED IN SAIDSHELL, SAID VENT BEING LOCATED IN THE LOWER TAIL PORTION OF SAID SHELLFOR ADMITTING AMBIENT WATER UNDER PRESSURE TO THE INTERIOR OF SAIDHOLLOW SHELL; OCEANOGRAPHIC INSTRUMENT MEANS ATTACHED TO THE LOWERPORTION OF SAID SHELL; A QUANTITY OF HIGHLY VAPORIZABLE SUBSTANCECARRIED INTERIORLY OF THE NOSE PORTION OF SAID HOLLOW SHELL ADAPTED TORELEASE A VOLUME OF HIGH PRESSURE GAS SUFFICIENT TO ESTABLISH A POSITIVEBUOYANCY OF SAID DEEP OCEAN BUOY ENABLING IT TO RETURN THE SAIDINSTRUMENTS TO THE SURFACE; AND SAID QUANTITY OF HIGHLY VAPORIZABLESUBSTANCE BEING CONTAINED IN AN INSULATED OPEN CONTAINER WHICH ISMOUNTED IN THE NOSE PORTION OF SAID SHELL.